Assume that cream has a specific heat of 2900 J/kg· ◦C and has the same heat of fusion (3.34 × 105 J/kg) and melting point as water, and that ice cream has a specific heat of 2200 J/kg· ◦C. If two kilograms of cream are initially at 10◦C, how much liquid nitrogen, which has a latent heat of vaporization of 2.00 × 105 J/kg, must be vaporized to cool, freeze, and further cool the cream to -10◦C? Assume that the liquid nitrogen is kept at 77 K, the temperature of its liquid-gas phase transition, and that the gas floats away into the room at that temperature (so no heat goes to heating up the nitrogen gas).

Assume that cream has a specific heat of 2900 J/kg· ◦C and has the same heat of fusion (3.34 × 105 J/kg) and melting point as water, and that ice cream has a specific heat of 2200 J/kg· ◦C. If two kilograms of cream are initially at 10◦C, how much liquid nitrogen, which has a latent heat of vaporization of 2.00 × 105 J/kg, must be vaporized to cool, freeze, and further cool the cream to -10◦C? Assume that the liquid nitrogen is kept at 77 K, the temperature of its liquid-gas phase transition, and that the gas floats away into the room at that temperature (so no heat goes to heating up the nitrogen gas).

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.39P: The tip of a soldering iron consists of a 0.6-cm- diameter copper rod, 7.6 cm long. If the tip must...

See similar textbooks

Similar questions

It takes 15 minutes to warm up from 10 C to 20 C in a room whose temperature is 30 C. Assuming Newton's law of cooling, how long would it takes to warm up from 10 C to 25 C?
There is a calorimeter composed of a thermally insulated container. Inside it are 1.2 kg of ice at −15 ∘C. How much mass of water at 60 ∘C needs to be added in the calorimeter for the final temperature to be 5 ∘C? If water vapor were introduced at 100 ∘C instead of water, how much mass of steam would have to be added for the final temperature to be 30 ∘C? What volume would the water vapor in the previous part occupy (before adding it to the calorimeter) if the pressure at which it is contained is 1.20 × 105 Pa? NOTE: The molar mass of water is 18 g / mol. ice = 2090 J / kg ∘C. water = 4180 J / kg ∘C. Lf, water = 3.33 × 105 J / kg. Lv, water = 2.26 × 106 J / kg
Properties of Pure Substancies What is the specific internal energy of water at 50 kPa and 20°C?
Steam expands reversibly in a cylinder behind a piston from 6 bar dry saturated, to a pressure of 0.65 bar. Assuming that the cylinder is perfectly thermally insulated, calculate the work done during the expansion per kilogram of steam
Calorimetry In a kitchen there are two identical pans that have been previously heated, one of the pans is filled with 1/2 liter of Water at 100◦C and the other with 1/2 liter of oil at 130◦C. After that, no there is more fire that keeps introducing heat to both liquids. In that instant, a person who had cut 300 grams of potato into small cubes at a temperature of 25◦C, decides to pour half the amount of potato in the boiling water and the other half in the burning oil. a) Determine the temperature of the thermal equilibrium between the pore potatoes in the water, and the same for nocao in the oil, considering each cases as isolated systems. (b) Explain why the thermal equilibrium temperatures in both cases are almost the same, mention the physical fundamentals that characterize that result. information in the image respectively: water density: oil density: specific heat of water: specific oil heat: specific heat of the potato:
How many kilograms of -5 °C ice per day will melt and evaporate to steam after adding a total of 7500 kJ/hr?
During the midday 2pm, the temperature of the water that is left out on a table is 18° If the temperature of the surrounding is 38°C and the water’s temperature heated up to 26°C at 2:25pm. After how many minutes will the water’s temperature be 32°C?
5kg of Steam at pressure of 4.9 bar is produced from water at 20°c. Determine the amount of heat supplied if the Steam is 0.9 dry.
Many gyms and health clubs have steam saunas, which are small steam-filled rooms. Traditionally, steam saunas have a container of heated rocks. A small ladle of water is poured on the rocks in order to make the steam. Using heat transfer explain how hot rocks can be used to make steam?
1.2kJ of work was done on a DIATOMIC ideal gas in a PERFECTLY INSULATED container. A. How much heat energy was transferred? B. What is the change in the internal energy of the system? C. Will the temperature increase or decrease during this process, and how much? D. What is the change in enthalpy?
Consider two systems A and B. System A contains 3000 kJ energy at 20oC, whereas system B contains 200 kJ energy at 50oC. What is the direction of heat transfer when they are brought in contact with each other?
Using 1st and 2nd law of thermodynamics for irreversible expansion of Krypton: Krypton (ideal monatomic gas) is confined in one-fourth of a 48-litre container. The other part of the container is evacuated. When the partition is removed, the gas expands and fills the whole container, while the system loses 400J of heat to the environment at 290K. It is found that in the final state, the Krypton is at p2 = 5.5bar, T2 = 400K. Is this process possible or not? (?k?????? = 83.8 kg/kmol)